This multidisciplinary project aimed to combine fundamental knowledge of plant growth and development with polymer science and engineering to create a novel, high-impact fertilizer of superior functionality with an inherent sustained delivery mechanism. In view of the substantial losses of fertilizer nitrogen in the environment, the specific goal of the project was to engineer a high-performance plant fertilizer (HPF) by encapsulating fertilizer nitrogen in a biopolymer matrix so it can be released over time as the matrix breaks down. Besides the fertilizer nitrogen, encapsulation matrices will also contain essential nutrients, growth stimulants, and biocontrol agents, as well as natural microbes that fix nitrogen and synthesize humic and growth promoting compounds for optimal performance. Sustained release of the active materials will be achieved via manipulation of biodegradation properties of the matrix polymer. When exposed to soil, microbes, humidity, and sunlight, the matrix polymers will degrade at a controlled rate, loosening the matrix and gradually releasing encapsulated agents over a long period. As opposed to multiple applications of a convention fertilizer, a single application of the HPF should be sufficient until the crop is harvested, not only saving time, energy, water, and overall cost, but also benefitting the environment. The long-term goal of this study is to conduct extensive field trials to assess the impact of the HPF formulation and evaluate its commercial viability.

Major Results

Developed and characterized the performance of a unique matrix that retained and supported microbial growth in vivo and delivered natural compounds in the vicinity of plants and their roots

Successfully tested microbial fertilizer in greenhouse studies and small field plots successfully, with results indicating superior performance of this microbial fertilizer as compared with controls as demonstrated by much healthier plants with higher biomass, root mass, and chlorophyll content

Filed a provisional patent with the United Stated Patent and Trademark Office with respect to matrix and certain fertilizer formulations

Provided training to 5-6 students and/or researchers and conducted a week-long workshop in Pakistan to transfer the technology to Pakistani scientists

In March 2009, Dr. Imam again visited NIFA. As a US government employee he was unable to obtain the necessary country clearance for official travel; therefore, motivated by his strong commitment to the project, he took personal leave and paid for his own travel to Pakistan in both 2008 and 2009. During this most recent visit, he presented a week-long training course on development of slow-release microbial fertilizer formulations to the institute's Soil Science Group. He also met with his counterpart Dr. Azam to monitor progress on the project objectives, assist with planning for the large-scale production of fertilizer for greenhouse and field studies, and discuss next steps in the research process. In addition, Dr. Imam presented a seminar to the entire NIFA research staff on bioproducts from renewable resources.

Dr. Farooq-e-Azam and a colleague had hoped to visit California in 2009 to learn the processing and production of encapsulation matrices, although these plans were thwarted by long funding delays on the Pakistani side. Meanwhile, work proceeded on developing new formulations for polymer matrices for microbial encapsulation and on identifying additional microbes for inclusion in the fertilizer being develop. Efforts were also under way to devise the most efficient and cost-effective methods for producing the fertilizer. Initial field trials of two engineered fertilizer formulations were conducted with several different vegetable crops, and the initial results have been very encouraging, with the engineered fertilizers producing plants with considerably better growth than conventional synthetic nitrogen fertilizer.

A joint patent on “Development of starch-gypsum based encapsulation matrix: novel chemistry and unique microstructure” (USDA-ARS Log # 221567) was filed, with Dr. Azam, Dr. Imam, and Dr. Gregory Glenn as co-inventors, and once the patent is registered a paper on the work will be submitted to the Journal of Controlled Release. As of early 2010, however, the patent was delayed pending results from additional field trials, which was postponed due to funding problems on the Pakistani side. As soon as those funds are released, Dr. Azam and Dr. Imam are eager to proceed with the trials and scale up pilot production of the engineered fertilizer in cooperation with the National Fertilizer Institute in Faisalabad. They have been in contact with two Pakistani fertilizer companies interested in acquiring the new technology once the patent is issued so that they can begin producing the new varieties for sale. An Italian manufacturer also expressed interest in signing a cooperative agreement to further develop the microbial formulation.

As an unexpected side benefit of this project, while working on the project-related experiments, scientists in NIFA discovered that under composting conditions, cellulosic biomass (consisting mostly of leaves, twigs and other agricultural discard) generated heat due to exothermic bioprocesses, raising the temperature of the compost quite significantly. By maintaining the moisture level and with added insulation, heat generated inside the compost was able to maintain the temperature of water in a metal (conductive) container up to 75o C (167o F) for a period of several weeks. This discovery could have an enormous impact on the lives of poor rural residents without access to electricity. At NIFA, Dr. Azam has assembled several functional units called “BioGeysers” of variable sizes (5 - 300 Liter capacities) for local testing, and he characterizes the results as astonishing. Upon perfection, this technology would be able to provide lukewarm to warm water to rural populations, particularly during the winter months, at little or no cost. No grant funds or resources were utilized for this work, as it is not directly related to the objectives outlined in the original project, but Dr. Azam has assigned a separate team of additional scientists and technicians on this project. A publication is expected to follow from this work as well.

Experimental evaluation on the biodegradation of the encapsulation matrix continued at USDA in 2008 along with work on development of microsclerotia for incorporation in the matrix as a bioinsecticide. In April 2008 Dr. Iman made a self-funded visit to Pakistan to monitor research progress and transfer the technology for making the fertilizer matrix. While at NIFA, he delivered a lecture on emerging trends in agriculture and met with three research groups at NIFA to discuss research and development in material science and bioproducts. He also took the opportunity to visit the Pakistan Fertilizer Institute and the University of Agriculture Faisalabad, two organizations that are cooperating on the project.